Improvement in combined knob-latch and look



@dumm itstre atrnt @time JOHN H. VICKERS, OF NORWICII, CONNECTICUT, ASSIGNOR TO NORWICH vLOCK COMPANY.

Letters Pimm No. 77,552, ma May 5, 1868; @mama Api-iz 22, 1868;

IMPROVEMENT IN COMBINED KNOB-LATCH AND LOCK. l

TO ALI. WHOM IT MAY CON CERN:

Be it known that I,JOHN H. VIOKERS, of Norwich, county of New London, and State of Connecticut, assigner to the Norwich Loek Company, have invented certain new and useful Improvements in Locks for Doors; and I do hereby declare that the followingis a full and exact description thereof.

My improved lock is adapted to be vused as a latchllock, and is constructed with the several attachments now in use, for adapting locks to be used both as locks to fasten the door securely against intruders, and also as a common latch orcatch, to hold the door againstwind and the like, during the day, in ordinary use.

My invention relates to certain means whereby the security of the lock is increased without seriously increasingthe expense, and without changing the general arrangement of the construction.

I will first describe what I consider the best means of carrying out'my invention, and will afterwards designate the points which I believ'e to be new. The accompanying drawings form a part ofl this specification.'

Figure 1 is a. back view of th'e interior 'of the lock. i

Fig. I, A, represents the 1atchlever,with the tumbler in a different position. It is the position which it will maintain when a wrong key is inserted.

Figure 2 is a cross-section on the line S S, in tig. 1.

Figure 3 represents a. modification, which willbeafterwards described.

Similar letters of reference indicate like parts in all the figures. The drawings show the novel parts,w'ith so much ot' the other parts as is necessary to indicate their relai tions thereto. l i

A is the casing; B, the bolt; C, theeperatingi-knob; D, the latch-lever; and E the shaft, carrying an arm, e, by the partial rotation of which,in one direction or the other, the latch-lever D is eitherlowered, so that its Catch, d, is entirely clear of the bolt B,and thus made of no etl'ect, or is'raised so as to firmly hold ythe bolt B, as may be desired. ,l t

The'construction and arrangement of Athe latch-lever D will be readily understood from the draw-ings. It is precisely the same as is described in the patent issued to Henry B. Tyler, dated August 16, 1865, lwith the exception of the provision for greater security no'w about to be described.

M isy a tumbler, turning on the pivot m, which-is inserted in the latch-leverD, as represented. A is astop or fence, lixed on the casing A, against which -the tumbler M strikes, and prevents the. opening of the lock unless the tumbler is allowed to rise to the right position by the insertion of the proper key, N. -The tumbler is actuated by a spring, P, so that it constantly tends to stand at a proper height to clear the fence A', but it stands so related to the key-hole that the key, in being inserted, is certain to touch and tilt it, causing it to assume temporarily the position shown in 1, A.

The key N is recessed atthe point n to a sutiicient extent to allow the tumbler M to resume its position, so as to clear the stop A when the lock is operated. If a key is inserted which is not sufficiently recessed at the point n, the tumbler will remain displaced, and will strike against the stop A, and prevent the operation of the lock.

Fig. 3 represents a modification of the form of stop A', and of thc adjacent end of the tumbler M. This, or any other well-known modification of the forms of tumblcrs, and of stops oiffences, may be adopted in my lock if preferred. 1

t will be readily seen that by fitting the key therefor, and increasing the thickness of the lock a very little, or by diminishing the thickness of the latch-lever D at that point, there may be two or more tumblers, M, mounted side by side, and required to stand at diil'erent elevations in order to allow the opening of the lock. I do not, however, consider such duplication ot' the tumblers to be generally necessary or advisable.

It results from my invention that the door-lock, with but the addition ot` the parts M and A', at a very' trilling cost, Vis made to operate, by the aid of the thin key N, with n degree o'f security which is sucient for all ordinary doors, and vastly greater than in locks of this character as heretofore used.

Having now fully described my invention, what I claim as new therein, and desire to secure by Letters Patent, is as follows:

I claim tlieemployrment of one or nlore tumblers, M, in combination with the latch-lever D in the Tyler lock, and adapted to operate relatively to the key N end stop A', or their equivalents, substantially as und for the purpose herein specified.

` JOHN H.`VICKERS. Witnesses:

FRANK A. SMITH,

JOHN R. THAYER. 

